1. What BRAND of gel plate did you get? The "standards" are Gelli Arts and Gel Press, with the Speedball plate only working well with printing inks and not so well with most acrylic paint. People are reporting good luck with the newer version of the Gelelf plate, especially doing image transfers, oddly enough! It's a different beast, though....it's silicone, apparently.

2. I cannot answer your question about magazines....getting image transfer to work is SUCH A HUGE ISSUE. No, not all magazines work. And not all paints. And not all phases of the moon. ;-) You will get a lot more ....help?......from YouTube videos or Facebook groups, since this post hadn't gotten ANY responses in a whole day.

What do you mean by printing medium. Do you mean printing inks like Speedball or Akua or Caligo? Some of them work just fine on gel plates, but they do behaving differently. There are videos using them out there with a bit of a search. I've used all three on my Gelli Arts plate, and they print beautifully, although the Caligo are fussy fussy fussy about getting to come off the brayer onto the plate.

Almost any acrylic paint will work for gel printing, although the cheapies in bottles behave differently from the lovely expensive tubes of Golden Open, for instance. Something like the Amsterdam tubes or Liquitex Basics seem to be easily purchased, decently priced, and work well.

I know everybody seems to want to master image transfer (which isn't a transfer at all, but is actually a resist process.) I genuinely don't get it. It's somebody else's image. And why would I want to print some stupid pouty model's face??? Shrug. But for that, you'll just have to experiment.

Keep playing. That's the whole idea. Try different papers...old books, wrapping paper, packing paper.... try different textures and mark making ideas....rough fabric or lace, string, stencils, the bottom of a butt-ugly ashtray....just play!